Friction drive unit



Jan. 4, 1966 R. DE MALLIE ETAL 3,226,951

FRICTION DRIVE UNIT Filed July 2. 1965 lioward R. De Mal lie Tilliam J D ieseL INVE TORS BY 17 M AITOkNEY 5 AGENT United States Patent 3,226,951 FRICTION DRIVE UNIT Howard R. De Mallie and William J. Diesel, Rochester,

N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Filed July 2, 1963, Ser. No. 292,304 Claims. (Cl. 64-30) The present invention relates to a drive unit for imparting the rotational movement of a driven shaft to a member freely rotatable on the shaft, and more particularly to a drive unit which is coupled to the shaft by means of a plurality of spherical members that also permit axial movement of the unit relative to the shaft.

In the winding of a strand or web on a reel or core, it is necessary that the tension on the strand or web is not unduly increased by the binding of the reel or core on its drive shaft. In a winding operation Where a plurality of reels or cores are arranged in contiguous or spaced relation on an arbor and keyed thereto for winding a plurality of strands or webs, each of which is wound on an individual reel or core, any axial shifting of the reels or cores on the arbor during the Winding operation often tends to bind such wind-up members on the arbor. As a result, abnormally high tension is applied to the material, which can damage it. Although this condition can be eliminated to a certain extent by winding at a reduced speed, it is evident that such a reduction in speed requires a greater time for winding equivalent amounts of material.

The driving unit disclosed and described hereinafter eliminates the objectionable characteristics of the drive assemblies of the prior art in that a unit is arranged on the shaft between each reel and is coupled to the drive shaft by a plurality of spherical elements which not only provide a suitable coupling of the drive unit to the shaft, but also permits the drive unit to shift axially without affecting the reels, thereby eliminating the binding condition described above. In addition, the drive unit can be mounted on a wind-up arbor in alternate relationship with the reels or cores that are also mounted on the arbor. Due to the friction drive surfaces of each drive unit, such surfaces permit engagement with adjacent reels or cores when they are positioned alternately on the arbor, thereby insuring a more positive driving action for each reel or core.

The primary object of the invention is to provide a drive unit which can be coupled to a splined arbor and which permits the drive unit to shift axially when any twisting or cocking torque is applied thereto by the material being wound.

Another object of the invention is to provide a drive unit for a splined arbor which can be readily mounted on the arbor between adjacent elements which are rotatably mounted on the arbor for wind-up of the product.

Still another object of the invention is to provide a drive unit which is relatively simple in construction for imparting rotation of a shaft to a member freely rotatable on the shaft and in engagement with the drive unit.

Still further objects and advantages of the invention will be apparent to those skilled in the art by the description which follows.

Reference is now made to the accompanying drawing in which like reference numerals designate like parts and wherein:

FIG. 1 is an elevation view of a wind-up arbor showing the relationship of the drive units and a number of reels on which the product is wound;

FIG. 2 is an enlarged sectional view showing the structure of the drive unit and the arrangement for coupling the drive unit to the arbor or shaft;

FIG. 3 is an end view of the drive unit showing the 3,226,951 Patented Jan. 4, 1966 arrangement of the means for coupling the drive unit to the arbor; and

FIG. 4 is a detail view showing the relationship of the arcuate keyways in the arbor and the spherical members for coupling the drive unit to the arbor.

With reference particularly to FIG. 1, a plurality of reels 10, each of which has a central hub 11, are arranged on an arbor 12 with a drive unit, designated generally by the numeral 13, arranged between each of the reels. The reels 10 and drive units 13 can be retained in an engaging relationship by any suitable means such as the retainer flanges used for holding a plurality of reels on an arbor as shown in US. Patent 2,755,029. The reels 10 are provided with an aperture 14 which can extend completely through the hub 11 or, if the hub is hollow, can be arranged only in the flanges 15 of each of the reels. Accordingly, the reels 10 are freely rotatable on the arbor 12 and have no driving connection therewith so as to be rotatable thereby when positioned or arranged on the arbor adjacent each other.

With reference to FIG. 2, the drive unit 13 comprises a sleeve 20 having a central flange 21, the portion of the sleeve on each side of the flange comprising a hub 22. The sleeve 20 is provided with a central aperture 23 for receiving the arbor 12 which is provided with a number of longitudinally extending arcuate grooves or keyways 24. The sleeve 20 is also provided with a number of equiangularly spaced recesses 25 which extend from one end of the sleeve toward the other end, but do not extend completely through the sleeve. These recesses. are equivalent in number and angularly spaced in accordance with the grooves 24 in the arbor 12. A number of spherical members or balls 26 are arranged in each of the recesses 25, and since these recesses subtend an angle greater than the balls 26 are retained in the recesses and cannot move radially so as to fall out of the recesses. As shown in F168. 2-4, the portions of the balls that extend beyond the recesses 25 engage the grooves 24 in arbor 12 and provide a means for coupling the sleeve to the arbor so that the rotation of the arbor is transmitted to the sleeve.

In order to retain the balls 26 in the recesses 25 and against any axial removal thereof, a retaining ring 27 is mounted in the end of sleeve 20 adjacent the open end of the recesses 25. This ring is provided with an aperture 28 and is retained in sleeve 20 by the portion 29 thereof that is staked over on said ring, as shown in FIG. 2.

A friction member 30, which can take the form of a washer, has an aperture 31 for receiving the hub 22 and an outer diameter such that the member is at least of the same diameter as flange 21, but preferably greater than flange 21, as shown in FIG. 2. The friction members 30 are retained in position on hubs 22 by a retaining ring 32 which can be of a commercially-available type, such as a Tru-Arc ring. Each of rings 32 is seated in an annular recess 33 formed in the outer periphery of each of hubs 22 in a manner well known to those skilled in the art. The friction member 30 is preferably provided with a ring 34 that is made of a commercially-available material, such as Neoprene, which can be bonded or secured in any other manner to its respective friction member 30. The outer surface 35 of the ring 34 preferably lies in. a plane that is beyond the end of the sleeve 20 so as to engage one of the reel flanges 15 and provide clearance for the end of the sleeve.

With reference to FIG. 4, the recesses 25 in sleeve 20 are formed by drilling or boring axial holes in the sleeve to such a depth that they do not go through the sleeve and which intersect the aperture 23 for receiving the arbor 12. Since the angle subtended by the arc in sleeve 20 is greater than 180, the balls 26 that are inserted therein cannot move in a radial direction. In order to insure proper engagement of the balls 26 with the arcuate keyways 24 in the'arbor 12, the radius of the arcuate keyways is made greater than that of the recesses 25 in the sleeve 20 and the angle subtended by the arcuate keyways 24 is therefore made less than 180. Since the balls 26 do not completely occupy the axial length of the recesses 25, the drive unit can move axially with respect to arbor 12 without causing any binding action of the drive unit on the arbor.

Since the drive unit comprising sleeve 20, friction members 30 and the rings 34 are a contained unit, such unit can be readily inserted or positioned on the arbor 12 and Will contact the arbor only through the balls 26 that are "retained in the recesses 25. When a group of drive units and reels are mounted on an arbor, as shown in FIG. 1, the rotation of shaft 12 is transmitted to sleeve 20 by balls 26, and this movement is then transmitted by the friction members 30 and rings 34 to the adjacent reels due to the thrust exerted by the retainer flanges that would be secured to arbor 12 as shown in the above-mentioned patent. Although the rings 34 have been described as being preferably of a material such as Neoprene, it should be obvious to those skilled in the art that any type of material having a high coefiicient of friction will provide the same results. Further, the invention is not to be limited to the embodiment disclosed in the drawings and described above, but is of a scope as defined by the appended claims.

We claim:

1. A drive unit positionable on a rotatable shaft and retainable in frictional engagement with at least one member that is freely rotatable on said shaft, said shaft having a number of angularly spaced, axial keyways adapted to be engaged by 'said drive unit for imparting the rotation of said shaft to said member, the combination comprising:

a sleeve having a central aperture for receiving said shaft, said aperture being provided with a number of axial recesses corresponding in number to said keyways;

means arranged in said recesses and engaging said keyways, when said unit is positioned on said shaft, for coupling said sleeve to said shaft and permitting axial movement of said sleeve relative to said shaft; and

means arranged on said sleeve and frictionally engaging the latter and said member when said member is positioned on said shaft adjacent said unit for transmitting the rotation of said sleeve to said member.

2. A drive unit in accordance with claim 1 wherein said coupling means comprises at least two balls arranged in each of said recesses.

3. A drive unit in accordance with claim 1 wherein said engaging means comprises a ring member frictionally engaging said sleeve and said member.

4. A drive unit positionable on a rotatable shaft and retainable in frictional engagement with at least one member that is freely rotatable on said shaft for imparting the rotation of said shaft to said member, said shaft being provided with a number of angularly spaced, axial keyways adapted to be engaged by said drive unit which are arcuate in shape and subtend an angle less than 180, the combination comprising:

a sleeve having a hub and a central flange, said hub being provided with a central aperture for receiving said shaft, and said aperture being provided with a number of equiangularly spaced, arcuate recesses corresponding in number to said keyways, extending axially from one end toward the other end of said sleeve and subtending an angle greater than 180;

a plurality of balls arranged in each of said recesses, the portions of said balls extending beyond said recesses engaging said keyways, when said sleeve is positioned on said shaft, for coupling said sleeve thereto and permitting axial movement of said sleeve re ati B? a d Shaft;

means fixed to said one end of said sleeve for retaining said balls in said recesses; and

friction members arranged on said hub adjacent each side of said flange for frictionally engaging the latter and said member when said member is positioned on said shaft adjacent said sleeve for transmitting rotation of said shaft to said member.

5. A drive unit in accordance with claim 4 including means arranged on each end of said hub for retaining said friction members on said hub.

6. A drive unit in accordance with claim 4 wherein the radius of the arcuate keyways in said shaft is larger than the radius of the arcuate recesses in said sleeve.

7. A drive unit in accordance with claim 4 wherein said recesses are closed at the other end of said sleeve and are of a length to permit said sleeve to move axially relative to said shaft.

8. A drive unit in accordance with claim 4 wherein each of said friction members includes a ring whose surface for engaging said member lies beyond the plane of the respective end of said sleeve.

9. A drive unit in accordance with claim 8 wherein said rings are a soft, plastic material having a high coefficient of friction and are bonded to said friction members.

10. A drive unit positionable on a rotatable shaft and retained in frictional engagement between two members freely rotatable on said shaft for imparting rotation thereto, said shaft being provided with a number of equiangularly spaced, axial keyways adapted to be engaged by said drive unit which are arcuate in shape and subtend an angle less than the combination comprising:

a sleeve having a hub and a central flange, said hub being provided with a central aperture for receiving said shaft, and said aperture being provided with a number of equiangularly spaced, arcuate recesses corresponding in number to said keyways, extending axially from one end toward the other end of said sleeve and subtending an angle greater than 180;

a plurality of balls arranged in each of said recesses and retained in a radial direction by said recesses, the portions of said balls extending radially from said recesses engaging said keyways, when said sleeve is positioned on said shaft, for coupling said sleeve thereto and permitting axial movement of said sleeve relative to said shaft;

a ring fixed to said one end of said sleeve for retaining said balls in said recesses;

friction members arranged on said hub adjacent each side of said flange, each friction member including a ring of plastic material having a high coefficient of friction for frictionally engaging said flange and said members when the latter are positioned on said shaft adjacent said sleeve, for transmitting the rotation of said sleeve to said members; and

a collar on each end of said sleeve for retaining its respective friction member on said sleeve.

References Cited by the Examiner 3 1918 Switzerland.

BROUGHTON G. DURHAM, Primary Examiner.

ROBERT C. RIORDON, Examiner. 

1. A DRIVE UNIT POSITIONABLE ON A ROTATABLE SHAFT AND RETAINABLE IN FRICTIONAL ENGAGEMENT WITH AT LEAST ONE MEMBER THAT IS FREELY ROTATABLY ON SAID SHAFT, SAID SHAFT HAVING A NUMBER OF ANGULARLY SPACED, AXIAL KEYWAYS ADAPTED TO BE ENGAGED BY SAID DRIVE UNIT FOR IMPARTING THE ROTATION OF SAID SHAFT TO SAID MEMBER, THE COMBINATION COMPRISING: A SLEEVE HAVING A CENTRAL APERTURE FOR RECEIVING SAID SHAFT, SAID APERTURE BEING PROVIDED WITH A NUMBER OF AXIAL RECESSES CORRESPONDING IN NUMBER TO SAID KEYWAYS; MEANS ARRANGED IN SAID RECESSES AND ENGAGING SAID KEYWAYS, WHEN SAID UNIT IS POSITIONED ON SAID SHAFT, FOR COUPLING SAID SLEEVE TO SAID SHAFT AND PERMITTING AXIAL MOVEMENT OF SAID SLEEVE RELATIVE TO SAID SHAFT; AND MEANS ARRANGED ON SAID SLEEVE AND FRICTIONALLY ENGAGING THE LATTER AND SAID MEMBER WHEN SAID MEMBER IS POSITIONED ON SAID ADJACENT SAID UNIT FOR TRANSMITTING THE ROTATION OF SAID SLEEVE TO SAID MEMBER. 